Action approach to cosmological perturbations: the second-order metric in matter dominance

Journal Article · Fri Aug 15 00:00:00 EDT 2008 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2008/08/028· OSTI ID:22156720

Boubekeur, Lotfi; Creminelli, Paolo; Vernizzi, Filippo ^[1]; Norena, Jorge ^[2]

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1. Abdus Salam ICTP, Strada Costiera 11, I-34014 Trieste (Italy)
2. SISSA/ISAS, Via Beirut 2, I-34014 Trieste (Italy)

We study nonlinear cosmological perturbations during post-inflationary evolution, using the equivalence between a perfect barotropic fluid and a derivatively coupled scalar field with Lagrangian [-({partial_derivative}{phi}){sup 2}]{sup (1+w)/2w}. Since this Lagrangian is just a special case of k-inflation, this approach is analogous to the one employed in the study of non-Gaussianities from inflation. We use this method to derive the second-order metric during matter dominance in the comoving gauge directly as a function of the primordial inflationary perturbation {zeta}. Going to Poisson gauge, we recover the metric previously derived in the literature.

• OSTI ID: 22156720
• Journal Information: Journal of Cosmology and Astroparticle Physics, Vol. 2008, Issue 08; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COSMOLOGY
DISTURBANCES
GALACTIC EVOLUTION
INFLATIONARY UNIVERSE
LAGRANGIAN FUNCTION
METRICS
NONLINEAR PROBLEMS
SCALAR FIELDS